Melting furnace



June 14, 1927. 1,632,366

W. H. CHEZNOWITIH ET AL.

MELTING FURNACE Filed Nov. 8, 1924 3 Sheets-Sheet 1 Elma V501;

rae a v I v 1632,366 J1me 1927' w. H. CHENOWITH ET AL 9;

MELTING FURNACE Filed Nov. 8, 1924 3 Sheets-Sheet 2 a 99 June w. H. CHENOWITH ET AL MELTING FURNACE Filed Nov. 1924 3 Sheets-Sheet 3 gvvuenlour Zao rsa e r am a/5714 Patented June 14, .1927.

T FFICE.

WILLIAM H. ennncwrrn AND GEORGE c. SCHIIVIPF, or centers BAY, MARYLAND, As-

srenoas TO HARRY n. HARVEY, or BALTIMORE, MARYLAND.

MELTING FURNACE.

Application filed November 8, 1924. Serial No. 748,675.

This invention relates to furnaces for melting soft metals, such as type metal. One purpose of the-invention is to provide an improved valve and valve operating means for controlling the outlet of metal from the melting pot. A further purpose of the invention is to provide moans wherebythe spout through which the molten metal is drawn from the melting pot may be swung into various positions to deliver the metal into a plurality of molds, and a further purpose of the invention is to provide convenient means for operating the disk or dasher for mixing the metal.

In the accompanying drawing,

Fig. 1 is a side elevation of the furnace, partly in central section;

Fig. 2 is a central section on the line Fig. 3 is a detail of the valve;

Fig. 4; is a top plan view of the furnace;

Fig. 5 is a section on the line 5-5 of Fig. 3; and,

Fig. 6 is a similar sectional view showing the spout in a different position.

Referring to the drawing, a indicates the furnace casing which is cylindrical in form and provided with gas burners 1, in its lower portion. A melting pot b is suspended from the top of the part 2 of the casing, and the flame and gases from the burners flow upwardly around the melting pot and through pipes 3 into an enlarged part 4 of the casing, above the melting pot, and thence escape to the atmosphere through a fine 5, controlled by a damper 6. The bottom of the melting pot is provided with an outlet opening in which is fitted a sleeve 7, having a valve seat in its upper end, and a valve 8 is adapted to rest on this seat and close the outlet from the melting pot. This outlet is substantially at the vertical axis of the melting pot and furnace casing, and a valve stem or rod 9 extends through the center of the top 10 of the furnace, for operating the valve. As shown in Fig. 3, the valve is loosely fitted to the valve stem and connected thereto by a pin 11, so that the valve can adjust itself to the valve seat. The valve stem is slidable in a sleeve g, which is threaded on to the sleeve 7 and projects upwardly into the melting pot, this sleeve 9 having perforations g through which the metal may flow from the pot through the valve sleeve 7 when the valve is raised. The valve stem is vtion of the parts of the link.

connected to a lever 12, which is centrally fulcrumed above the furnace in a bearing 13. The arm 12 of the lever, to which the valve stem is pivoted, is provided with a counterweight 14, and to the opposite arm 1 12 of the lever is connected a link 15, which is attached to a hand lever 16, pivotally mounted at 17 in a bracket 18 on the side of-the furnace, casing. The link is composed of two parts, one of these, 15 consisting of a rod pivotally fastened to the lever 12, and the other part 15 consisting of a yoke pivoted to the lever 16 and having an opening through which the rod 15 extends, sothat thepart 15 may slid-e within the part 15 Between the part 15 and an adjustable stop 15 on the rod 15 is arranged a compression spring 15, tending to force the two parts of the link apart. A nut 15 on the lower end of the rod prevents the separa- This construction forms an expansion joint in the link. It willbe evident that when the hand lever 16 is moved upwardly, the link will be raised and the lever 12 will be rocked by the weight 1 1 and the valve stem will be forced downward, causing the valve to seat in the outlet opening of the melting pot. When the valve is closed, the hand lever is locked in its raised position by the locking pin 19 in the bracket 18, to prevent the valve from being opened through accidental or careless. operation of the hand lever. j

When the furnace is in use, the valve stem, of course, becomes very hot and will expand, and the function of the expansion joint in the link is to permit the lever 12 to rock when the valve stem expands.

A spout 20 has an elbow 20 one end of which is swiveled about the lower end of the valve sleeve 7, and the spout extends from the opposite side of said elbow through a slot 21, extending horizontally in the wall 2 of the furnace, and also through an opening 22 in a sliding covering 0, which closes said opening. This sliding cover is composed of a central section 23 and end sections 24 and 25, these sections being slidable in flanged guides 26 and 27, arranged above and below the slot and extending for a considerable distance beyond the ends of the slot. The spout 20, with this arrangement, may be swung to any position between theends of the slot in order to deliver the metal into a Ill) plurality of molds, and in any position of the spout the slot in the furnace casing will remain covered or closed. The cover 0 might be made in one piece of sufficient length to cover the slot in any position of the spout; but this would require a very long one-piece coverwhich would be difficult to move and which also might interfere with other parts around the furnace wall. Therefore, the cover for theslot is made in three sections. The :entral section 23 hasflanges 28 at it: ends, and the sections 24: and 25 have flanges 24 and 25, respectively, arranged between the flanges 23 so that when the central section is moved in one direction, it will pull the end section 24 after it and will slide upon the section 25 without moving the latter, as illustrated in Fig. 6. lVhen the spout is moved in the opposite direction, the central section will pull the section 25 over the adjacent end of the slot and the spout 20 will engage the flanged end of the section 24 and move the latter back to the position shown in Fig. 5., wherethe flanged end of said sec tion is in registry with the end of the slot. The central section is slightly longer than the slot so that in the intermediate position of the spout, shown in Fig. 5, said section will close the slot, and when the spout is moved in one direction or the other from the center, one of the end sectionswill move with the central section and thus the slot in the casing will be closed at all times.

The dasher or mixing disk It has a central sleeve which slides upon the valve stem, and thi sleeve has a cross-bar 31 to which two parallel rack rods 32 are secured. These 'ro'ds extend through the top plate of the furnace and are engaged by pinions 33, upon a horizontally extending shaft 34 which, as shown, is geared to a shaft 35 which extends downwardly at the side of the furnace casing and is geared to a shaft 36 upon which is a hand wheel 37, by which the shafts and gears may beturned. By turning the wheel 37, the

rack rods and the mixing disk may be raised or lowered, as will be evident. The arrangement of the operating wheel at the side of the casing is an improvement over prior devices where the operating mechanism for the mixing plate has usually been arranged at the top of the furnace and difiicult of access.

It is believed that the operation of the furnace will be clear from the foregoing without any further detailed statement of operation.

What we claim is:

1. In a melting furnace, a casing, a melting pot within the casing and having an outing pot within the casing and having an out- J let opening in its base and a valve seat in said opening, a valve stem extending downwardly through the pot and having a valve at its lower end adapted to fit on said seat when the stem is lowered, a lever fulcrumed on the top of the furnace'and having a pivotal connection with said stem, a hand lever pivoted to one side of the furnace, a link connecting said levers, said link comprising two parts and a yielding connection between said parts, and means for locking the hand lever when the valve is seated.

In testimony whereof we hereunto affix our signatures.

WILLIAM H. CHENOVVITH. GEORGE C. SCHIMPF. 

